Cap wire catcher



Se t. 5, 1967 T. RODRIGUEZ CAP WIRE CATCHER Filed March 5, 1966 a mu m MR w N IR m 0. r m w 4 T H A m R X H T k T II I I) l V1 A W T F B P m M m United States Patent ABSTRACT OF THE DISCLOSURE A cap wire catcher for catching cap wire ejected from electrically detonated blasting operations within a borehole. Said cap wire catcher comprises a tubular frame, a borehole engaging means attached to the frame, a deflector means, and a means for attaching the deflector means at an angle to a plane normal to the axis of the frame and intersecting the axis of the frame.

This invention relates to a method and apparatus for catching cap wire when explosives are detonated electrically within a borehole.

The term cap wire as used in this specification means an insulated wire having two conducting members which are enclosed in a common insulated casing or two separate insulated wires without the enclosed casing. The wires are attached on one end to an electrical blasting cap and on the other end to an electrical source, such as a battery. When the battery circuit is closed electrical current is passed through the cap wire and through the electrical blasting cap wherein said blasting cap is detonated thereby causing the explosive to be detonated.

The apparatus of this invention is intended to act as a safety device for use near electrical high lines where unrestricted flying cap wire is recognized as a serious threat to safety and in other areas where unrestricted flying cap wire would be dangerous, such as highly populated areas.

The apparatus disclosed in this specification is an improvement over what is presently in use. The method most commonly used today is to place a heavy weight over the borehole wherein the explosive is to be detonated. One disadvantage in using the heavy weight is that it is cumbersome and requires the use of extra personnel to position it. The device of the present invention, on the other hand, is relatively light and easy to position by a single operator.

The primary object of the invention is to provide an apparatus which can catch a cap wire from an explosive blast within a borehole.

Another object of the invention is to provide a cap wire catcher which is light weight and easy to position.

A further object of the invention is to provide an apparatus which is capable of ensnaring the cap wire and deflecting other material from the borehole at an angle to a plane normal to the axis of the borehole when an explosive charge is detonated within the borehole.

This invention features a cap wire catcher having a tubular body with spikes attached at one end for engaging the walls of a borehole and a deflector attached at the other end of the tube and at an angle to a plane normal to the axis and intersecting the axis of the tube.

Another feature of this invention is a cap wire catcher having a tube cut in half lengthwise and hinged along one cut and having a first and second end, an adjusting means attached to opposing edges of the unhinged cut of the tube, a plurality of spikes attached in spaced relationship to the outside wall of one end portion of the tube for engaging the earth, a bar attached near the center of the tube for supporting the cap wire catcher prior exiting said tube.

Among the important advantages of the new cap wire catcher is its ease of installation by a single operator. In its preferred form, the device weighs approximately 45 pounds and is about 44 inches in length.

The above and other objects, features, and advantages of the present invention will be more fully understood from the following description considered in connection with the accompanying illustrative drawings wherein:

FIGURE 1 is a frontal perspective view of the cap wire catcher prior to insertion in a borehole.

FIGURE 2 is a rear view of the cap wire catcher shown in FIGURE 1.

FIGURE 3 is a cross-sectional view of the earth showing the cap wire catcher in fullview and showing the explosive charge and the accompanying ca-p wire and battery circuit for detonating said charge.

- Referring now to the drawings and in particular to FIGURE 1, a cylindrical tube 10 has a longitudinally unhinged cut formed by edges 11 and is adjustably connected at the unhinged cut by a threaded screw and nut arrangement 14. One end of the tube 10 is encircled by a collar 12. A plurality of spikes 18 are attached near the end of tube 10 which is opposite collar 12. A support bar 16 is attached to tube 10 at a point between threaded screw and nut arrangement 14 and spikes 18. A heavy wire mesh deflector 22 is attached to tube 10 by means of a deflector support bar 20.

In FIGURE 2 a tube 10 has a longitudinal cut through its diameter which extends from end to end of said tube and a hinged surface 30 along the side of said tube opposite the unhinged cut formed by edges 11.

The invention in FIGURE 3 operates by placing a cap wire catcher assembly 10 in a borehole 42 which has been previously drilled in a portion of earth 40 so that a support bar 16 rests upon the portion of earth surrounding the top of the 'borehole. Cap wire catcher assembly 10 is then anchored in the borehole 42 by expanding adjusting screw and nut assembly 14 until the engaging spikes 18 are firmly imbedded in the walls of the borehole 42. A cap wire 46 is then attached to an electrical blasting cap 43 which was inserted in an explosive package 44. Explosive package 44 is dropped in borehole 42 and the remaining end of cap wire 46 is attached to a battery 48. When the circuit is completed by closing a switch 50, the charge is detonated whereupon cap wire 46 is forceably ejected from borehole 42 by the blast and becomes ensnared by deflector 22 thereby preventing the flying cap wire from causing damage in the surrounding area.

It is obvious that the explosive could be placed in the borehole 42 prior to securing the cap wire catcher at the top of the borehole in which case the free end of wire 46 would either be fed through the inside of the cap wire catcher assembly 10 or through the slot formed by edges 11 in which case bolt assembly 14 and collar 12 would have to be removed during insertion of the wire. If the latter becomes the preferred use, the nut assembly 14 can be pivoted with one side slotted to facilitate easy removal of the bolt. Collar 12 must also have a disengagement means, such as a snap lock.

It will be obvious to those skilled in the art that many other changes and modifications of the invention may be made without departing from the true scope thereof as defined in the appended claims.

What is claimed is:

1. A cap wire catcher comprising a tube cut in half lengthwise and hinged along one cut and having a first and second end, an adjusting means attached to opposing edges of the unhinged cut of said tube, a plurality of spikes attached in spaced relationship to the outside wall of said first end portion of said tube, a support means attached to said tube, a means for rigidly securing the unhinged cut of said tube at said second end, a deflector means, and a means for attaching said deflector means at an angle to a plane normal to the axis of said tube and intersecting the axis of said tube.

2. A cap wire catcher as described in claim 1 wherein the deflector is made of Wire mesh.

3. A cap wire catcher as described in claim 1 wherein the support means is a bar attached perpendicularly to said tube and below said adjusting means substantially midway between said ends of said tube.

4. A cap wire catcher as described in claim 1 wherein the means for rigidly securing the unhinged cut is a collar encircling said second end.

5. A method of catching a cap wire which is ejected firom an electrically detonated explosion within a borehole comprising:

(a) inserting a cap wire catcher in a borehole, said cap wire catcher having a tube cut in half lengthwise and hinged along one cut and having a first and second end, an adjusting means attached to the opposing edges of the unhinged cut of said tube, a plurality of spikes attached in spaced relationship to the outside wall of said first end portion of said tube, a deflector means, and a means for attaching said deflector means at an angle to a plane normal to the axis of said tubular frame and intersecting the axis of said tubular frame;

(b) expanding said tube until said plurality of spikes engage the wall of said borehole;

(c) detonating an explosive electrically within said borehole by passing an electric current through a cap wire; and

(d) catching the-cap wire with the deflector means as said cap wire exits the borehole following detonation of said explosive.

References Cited UNITED STATES PATENTS 2,387,770 10/1945 Rogers 102-22 2,401,140 5/ 1946 Cordie 102-24 2,407,442 9/ 1946 Parr 10222 2,472,997 6/ 1949 Williams 102-22 2,755,734 7/ 1956 Smith 102-22 2,871,785 2/1959 Hintze et al 10222 BENJAMIN A. BORCHELT, Primary Examiner.

V. R. PENDEGRASS, Assistam Examiner. 

1. A CAP WIRE CATCHER COMPRISING A TUBE CUT IN HALF LENGTHWISE AND HINGED ALONG ONE CUT AND HAVING A FIRST AND SECOND END, AN ADJUSTING MEANS ATTACHED TO OPPOSING EDGES OF THE UNHINGED CUT OF SAID TUBE, A PLURALITY OF SPIKES ATTACHED IN SPACED RELATIONSHIP TO THE OUTSIDE WALL OF SAID FIRST END PORTION OF SAID TUBE, A SUPPORT MEANS ATTACHED TO SAID TUBE, A MEANS FOR RIGIDLY SECURING THE UNHINGED CUT OF SAID TUBE AT SAID SECOND END, A DEFLECTOR MEANS, AND A MEANS FOR ATTACHING SAID DEFLECTOR MEANS AT AN ANGLE TO A PLANE NORMAL TO THE AXIS OF SAID TUBE AND INTERSECTING THE AXIS OF SAID TUBE. 